"They all have fun together. They've always been really cool with each other and [Beyoncé and Jay Z] like being around Solange and her friends," says the source.

Beyoncé and Jay Z, 44, recently released a star-studded trailer for their summer tour, which kicks off on June 25. And another source adds Solange is busy working on her new album and with her role as art director for PUMA.